Image-capturing apparatus and image-capturing method

ABSTRACT

An image-capturing apparatus includes an image-capturing unit configured to capture image data of a subject and to store the captured image data in an image-capturing operation; a speed detector configured to detect speed information; and a controller configured to control the image-capturing unit so that, in an automatic image-capturing process that is not based on a shutter operation of a user, a distance moved by the image-capturing apparatus is computed on the basis of information from the speed detector, and the image-capturing operation is performed in response to the fact that a computation result indicating that the image-capturing apparatus has moved a predetermined distance is obtained.

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Japanese PatentApplication JP 2007-216669 filed in the Japanese Patent Office on Aug.23, 2007, the entire contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image-capturing apparatus and animage-capturing control method. More particularly, the present inventionrelates to an image-capturing apparatus for performing drive log imagecapturing and life log image capturing as automatic image capturing.

2. Description of the Related Art

For example, as a drive log camera, a camera which is disposed inside anautomobile has been considered, in which still images are capturedperiodically, and thereby a user records scenery in the travelingdirection and inside the car as image data while driving the car.Furthermore, in addition to image capturing of still images, a camerafor capturing moving images has also been considered. Furthermore, acamera of a type, which is also called a life log camera or a life slicecamera, which is worn by a user himself/herself, and in which imagecapturing is periodically performed to capture an activity history ofthe user, has also been considered.

By using the drive log camera and the life log camera, it is possible torecord, as image data, the activity history and memories of the userwhen the user moves by an automobile, on foot, or the like.

In Japanese Unexamined Patent Application Publication No. 2007-109049,an apparatus is proposed in which images of the surroundings of a user'svehicle are captured using a camera disposed in the user's vehicle, anedge extraction process is performed on camera images when the user'svehicle is stopped and on camera images when the user's vehicle startsmoving in order to detect an object. When an object is detected, thecamera image at the departure time is displayed on a display device, andwhen an object is not detected, the camera image at the departure timeis not displayed.

SUMMARY OF THE INVENTION

When, as a drive log camera and a life log camera, an apparatus isconsidered in which an image-capturing apparatus is disposed in anautomobile, a small image-capturing apparatus, which is mounted in aneyeglass-type or headgear-type wearing unit, is worn by a user, imagecapturing is performed at fixed time intervals, captured image data isstored, and distance intervals as places where image capturing has beenperformed become uncertain depending on the movement speed of theautomobile and the user.

FIG. 15 shows the relationship between an image-capturing distanceinterval and the speed of the image-capturing apparatus when, forexample, image capturing is performed at fixed time intervals in animage-capturing apparatus disposed in an automobile. The image-capturingapparatus is disposed in the automobile, and therefore, the speed of theimage-capturing apparatus, referred to herein, is the traveling speed ofthe automobile.

As shown in FIG. 15, if the speed is low, the distance moved during theperiod of a fixed time interval as an image-capturing time is small andtherefore, the image-capturing distance interval becomes small. If thespeed is high, the moved distance during a fixed time interval is largeand therefore, the image-capturing distance interval becomes large.

FIG. 16A shows changes in the speed of the image-capturing apparatus. InFIG. 16A, the horizontal axis indicates the speed and the horizontalaxis indicates the time.

FIG. 16A shows the speed of the image-capturing apparatus in responseto, for example, changes in the speed of the automobile. In this case,first, the automobile transits at a low speed, the speed graduallyincreases, and after a while, the automobile transits at a high speed.

Then, at this time, the image-capturing apparatus automatically capturesimages of a subject at time intervals as time periods T and stores thecaptured image data.

In FIG. 16A, times at which captured image data to be stored has beencaptured are indicated as points in time P1 to P9. The time period Tshould preferably be determined as a certain time period of between, forexample, approximately 5 to 60 seconds.

FIG. 16B shows distance intervals between places at which imagecapturing is performed when image capturing is performed at theintervals of the time period T as shown in FIG. 16A. Here, theimage-capturing distance intervals between image-capturing places atpoints in time P1 to P9 at which capturing of image data was performedare denoted as distances L1 to L5.

As shown in FIG. 16A, the speed was constant in the period betweenpoints in time P1 to P4 at which images of a subject were captured.Therefore, all the image-capturing distance intervals forimage-capturing places between points in time P1 and P2, between pointsin time P2 and P3, and between points in time P3 and P4 are set to adistance L1, as shown in FIG. 16B. At points in time P1 to P4, imagecapturing is performed at places which are the same distance interval.

However, as shown in FIG. 16A, as the speed gradually increases betweenpoints in time P4 to P7, the distance intervals between image-capturingplaces gradually increase as shown by a distance L2, a distance L3, anda distance L4 in FIG. 16B.

The image-capturing apparatus moves at the highest speed between pointsin time P7 to P9. For this reason, the distance intervals between theimage-capturing places at points in time P7, P8, and P9 are longdistance intervals like a distance L5.

As described above, when image capturing is performed at fixed timeintervals in the image-capturing apparatus, distance intervals as placesat which capturing of image data to be stored is to be performed are notfixed due to changes in the speed of the image-capturing apparatus, andimage capturing is performed at distance intervals corresponding to thespeed of the image-capturing apparatus.

Here, when image capturing is performed to record a drive log or a lifelog, as one way of accurately storing a driving history and an activityhistory as images, performing of image capturing at places separated byfixed distance intervals that are as constant as possible has beendemanded.

Accordingly, it is desirable to perform image capturing at places atapproximately fixed distance intervals when image data to be stored isautomatically captured in the image-capturing apparatus.

According to an embodiment of the present invention, there is providedan image-capturing apparatus including: image-capturing means forcapturing image data of a subject and for storing the captured imagedata in an image-capturing operation; speed detection means fordetecting speed information; and control means for controlling theimage-capturing means so that, in an automatic image-capturing processthat is not based on a shutter operation of a user, a distance moved bythe image-capturing apparatus is computed on the basis of the speedinformation from the speed detection means, and the image-capturingoperation is performed in response to the fact that a computation resultindicating that the image-capturing apparatus has moved a predetermineddistance is obtained.

The control means may set a shortest waiting time period as a timeperiod from the time when the image-capturing operation is performed inthe image-capturing means, and if the shortest waiting time period hasnot passed when the computation result indicating that theimage-capturing apparatus has moved the predetermined distance isobtained on the basis of the speed detection information from the speeddetection means, the control means may cause the image-capturing meansto perform an image-capturing operation after the shortest waiting timeperiod has elapsed.

The control means may set a longest waiting time period as a time periodfrom the time when the image-capturing operation is performed in theimage-capturing means, and when the longest waiting time period haspassed before the computation result indicating that the image-capturingapparatus has moved the predetermined distance is obtained on the basisof the speed detection information from the speed detection means, thecontrol means may cause the image-capturing means to perform animage-capturing operation in response to the passage of the longestwaiting time period.

The control means may set a shortest waiting time period and a longestwaiting time period as time periods from the time when theimage-capturing operation is performed in the image-capturing means, ifthe shortest waiting time period has not passed when the computationresult indicating that the image-capturing apparatus has moved thepredetermined distance is obtained on the basis of the speed detectioninformation from the speed detection means, the control means may causethe image-capturing means to perform an image-capturing operation afterthe shortest waiting time period has elapsed, and when the longestwaiting time period has passed before the computation result indicatingthat the image-capturing apparatus has moved the predetermined distanceis obtained on the basis of the speed detection information from thespeed detection means, the control means may cause the image-capturingmeans to perform an image-capturing operation in response to the passageof the longest waiting time period.

When the computation result indicating that the image-capturingapparatus has moved the predetermined distance is obtained on the basisof the speed detection information from the speed detection means, thecontrol means may instruct a change of an image size in theimage-capturing operation of the image-capturing means on the basis ofthe time period elapsed after the image-capturing operation is performedin the image-capturing means.

When the computation result indicating that the image-capturingapparatus has moved the predetermined distance is obtained on the basisof the speed detection information from the speed detection means, thecontrol means may instruct a change of a compression ratio in theimage-capturing operation of the image-capturing means on the basis ofthe time period elapsed after the image-capturing operation is performedin the image-capturing means.

When a computation result indicating that the image-capturing apparatushas moved the predetermined distance is obtained on the basis of thespeed detection information from the speed detection means, the controlmeans may instruct a switching between a still-image capturing operationand a moving-image capturing operation as the image-capturing operationof the image-capturing means on the basis of the time period elapsedafter the image-capturing operation is performed in the image-capturingmeans.

According to another embodiment of the present invention, there isprovided an image-capturing method for use with an image-capturingapparatus for performing an automatic image-capturing process that isnot based on a shutter operation of a user, the image-capturing methodincluding: detecting speed information; computing a distance moved bythe image-capturing apparatus on the basis of the speed information inthe speed detection; and capturing image data of a subject and storingthe captured image data in an image-capturing operation in response tothe fact that a computation result indicating that the image-capturingapparatus has moved a predetermined distance is obtained.

According to the embodiments of the present invention, the distancemoved by the image-capturing apparatus is computed, and animage-capturing operation is performed in response to theimage-capturing apparatus being moved a predetermined distance. Thescenery at places separated by approximately fixed distance intervalsare stored by automatic image capturing. The movement distance may bedetermined by computation of the detected speed of the image-capturingapparatus and the movement time period.

Furthermore, if the movement speed is too high, times at which a fixeddistance interval is reached frequently occur. When the automobile isstopped, a time at which a fixed distance interval will be reached willnot occur for a long time. Therefore, basically, image capturing isperformed at times that correspond to fixed distance intervals and also,a shortest waiting time period and a longest waiting time are set, sothat the above cases can be appropriately dealt with.

According to the embodiments of the present invention, in a case inwhich automatic image capturing for, for example, a drive log and a lifelog is performed using an image-capturing apparatus installed in avehicle or worn by a user, an image-capturing operation is performed inresponse to the detection that the image-capturing apparatus has moved apredetermined distance. As a consequence, it is possible to performimage capturing for places at approximately fixed distance intervalsregardless of the movement speed of the vehicle and the user. As aresult, it is possible to store images appropriate for the vehicle andan activity history of the user.

Furthermore, if a shortest waiting time period and a longest waitingtime period are set and image-capturing times are set, it is possible toperform an appropriate image capturing in such a manner as to cope witha case in which the movement speed is too high or too low.

Furthermore, the time interval from the time of the previous imagecapturing until the time of the next image capturing varies in responseto a movement speed. If the size of an image to be captured and thecompression ratio thereof are changed in response to the situation andswitching between still-image capturing and moving-image capturing isperformed, it is possible to store captured image data appropriate for amoving situation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B, and 1C are illustrations of examples of the exterior of animage-capturing apparatus according to an embodiment of the presentinvention;

FIG. 2 is a block diagram of the image-capturing apparatus according tothe embodiment of the present invention;

FIGS. 3A and 3B are illustrations of an automatic image-capturingprocessing operation example I according to the embodiment of thepresent invention;

FIG. 4 is a flowchart of the automatic image-capturing processingoperation example I according to the embodiment of the presentinvention;

FIG. 5 is a flowchart of an automatic image-capturing processingoperation example II according to the embodiment of the presentinvention;

FIG. 6 is a flowchart of an automatic image-capturing processingoperation example III according to the embodiment of the presentinvention;

FIG. 7 is a flowchart of an automatic image-capturing processingoperation example IV according to the embodiment of the presentinvention;

FIG. 8 is an illustration of an automatic image-capturing processingoperation example V according to the embodiment of the presentinvention;

FIG. 9 is an illustration showing the automatic image-capturingprocessing operation example V according to the embodiment of thepresent invention;

FIG. 10 is a flowchart of the automatic image-capturing processingoperation example V according to the embodiment of the presentinvention;

FIG. 11 is an illustration of an automatic image-capturing processingoperation example VI according to the embodiment of the presentinvention;

FIG. 12 is an illustration of the automatic image-capturing processingoperation example VI according to the embodiment of the presentinvention;

FIG. 13 is a flowchart of the automatic image-capturing processingoperation example VI according to the embodiment of the presentinvention;

FIG. 14 is a flowchart of an automatic image-capturing processingoperation example VII according to the embodiment of the presentinvention;

FIG. 15 is an illustration of an automatic image-capturing process inthe image-capturing apparatus of the related art; and

FIGS. 16A and 16B are illustrations of the automatic image-capturingprocess in the image-capturing apparatus of the related art.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention will be described below. Thedescription will be given in the following order.

-   1. Exterior of Image-Capturing Apparatus-   2. Example of Configuration of Image-Capturing Apparatus-   3. Automatic Image-Capturing Processing Operation Example I-   4. Automatic Image-Capturing Processing Operation Example II-   5. Automatic Image-Capturing Processing Operation Example III-   6. Automatic Image-Capturing Processing Operation Example IV-   7. Automatic Image-Capturing Processing Operation Example V-   8. Automatic Image-Capturing Processing Operation Example VI-   9. Automatic Image-Capturing Processing Operation Example VII-   10. Modification

1. Exterior of Image-Capturing Apparatus

As an image-capturing apparatus 1 according to an embodiment of thepresent invention, various kinds of forms are conceived. Examples of theexterior thereof are shown in FIGS. 1A, 1B, and 1C.

FIG. 1A shows the image-capturing apparatus 1 of a type to be installedinto an automobile. The image-capturing apparatus 1 has a fixationmechanism for mounting on, for example, a dashboard, and is disposed onthe dashboard by means of a screw, a bolt, a bonding tape, or the like,as shown in the figure. At this time, an image-capturing lens 3Lprovided in the image-capturing apparatus 1 should preferably bedisposed so as to be capable of capturing an image by assuming thetraveling direction (toward the front) of the automobile to be a subjectdirection.

Although not shown in the figure, a display unit used to monitor orreproduce captured images may be provided in, for example, the back partof the image-capturing apparatus 1.

The image-capturing lens 3L may be disposed in such a manner that thedirection of the image-capturing lens 3L is directed toward the insideof the automobile so that image capturing is performed by assuming,rather than the traveling direction of the automobile, the inside of theautomobile as a subject direction.

FIG. 1B shows the image-capturing apparatus 1 of a neck hanging type.The image-capturing apparatus 1 has a part with which, for example, astrap is fixed, and is mounted in such a manner that the strap is fixedin that part and is hung around the user's neck. A user shouldpreferably wear it so that the image-capturing lens 3L provided in theimage-capturing apparatus 1 can perform image capturing by assumingtoward the front of the user to be a subject direction.

Similarly to FIG. 1A, although not shown in FIG. 1B, a display unit usedto monitor and reproduce captured images may be provided in the backpart of the image-capturing apparatus 1.

FIG. 1C shows the image-capturing apparatus 1 that is formed as aneyeglass-type display camera. The image-capturing apparatus 1 has, forexample, a mounting unit of a frame structure that half-circles fromboth-side head part toward the back head part, and is attached to theuser as a result of being hung around both auricles, as shown in thefigure.

In this image-capturing apparatus 1, in a state in which the user hasworn the image-capturing apparatus 1, the image-capturing lens 3L isarranged toward the front in such a manner that image capturing isperformed by assuming the field-of-view direction of the user to be asubject direction.

Furthermore, in the worn state shown in the figure, a pair of displayunits 5 and 5 for the left eye and the right eye are arrangedimmediately before both eyes of the user, that is, at a place where thelenses in normal eyeglasses are positioned. For the display units 5, forexample, a liquid-crystal panel is used, and by controllingtransmittance, a through state shown in the figure, that is, atransparent or semi-transparent state can be formed. As a result of thedisplay units 5 being made to be a through state, even if the user wearsthe image-capturing apparatus 1 like eyeglasses at all times, no problemis posed in ordinary life.

A pair of display units 5 are provided so as to correspond to both eyesand also, one display unit 5 may be provided so as to correspond to oneeye. In addition, the display units 5 may not be provided.

Up to this point, in FIGS. 1B and 1C, the neck-hanging type oreyeglass-type image-capturing apparatus 1 has been shown. Anotherconfiguration for the user to wear the image-capturing apparatus 1 isalso possible. Any type of mounting unit, such as, for example, aheadphone-type, neck-band-type, or behind-the-ear type, may be worn bythe user. In addition, a form may also be possible in which theimage-capturing apparatus 1 is worn by the user in such a manner thatthe image-capturing apparatus 1 is mounted in ordinary eyeglasses orvisor, a headphone, or the like by using fixture such as a clip.Furthermore, the image-capturing apparatus 1 may not necessarily bemounted in the head part of the user.

In the case of FIG. 1B, the image-capturing direction is set as beingtoward the front of the user. Alternatively, the image-capturingapparatus 1 may also be worn in such a manner as to be hung around theneck so that image capturing is performed for the area behind the userwhen it is worn.

Then, in the case of FIG. 1C, the image-capturing direction is set as afield-of-view direction. In addition, a configuration in which theimage-capturing lens 3L is mounted so that image capturing of an areabehind the user, an area at a side of the user, an area above the user,an area in a downward direction toward the feet, and the like when theimage-capturing apparatus 1 is worn, and a configuration in which aplurality of image-capturing systems whose image-capturing directionsare the same or different are provided.

Furthermore, in FIGS. 1A, 1B, and 1C, an image-capturing directionvarying mechanism with which the subject direction can be variedmanually or automatically may be provided for one or a plurality ofimage-capturing lenses 3L.

As an image-capturing apparatus for capturing an image, of course, formsother than those shown in FIGS. 1A, 1B, and 1C are possible. Forexample, a device, an example of which is a mobile phone, a PDA(Personal Digital Assistant), or a portable personal computer, and whichis provided with a function of an image-capturing apparatus, can beconceived as the image-capturing apparatus 1 of this embodiment.

Furthermore, in the above various forms, for example, a microphone forcollecting outside sound may be provided, so that an audio signal thatis recorded together with image data can be obtained. Furthermore, aspeaker unit for performing audio output and an earphone unit may alsobe formed.

Furthermore, a light-emitting unit for performing illumination in thesubject direction in the form of, for example, an LED (Light EmittingDiode), may be provided in the vicinity of the image-capturing lens 3L,or a flash light-emitting unit for capturing an image may be provided.

2. Example of Configuration of Image-Capturing Apparatus

At this point, an example of the configuration of the image-capturingapparatus 1 according to the embodiment of the present invention will bedescribed.

FIG. 2 is a block diagram showing the internal configuration of theimage-capturing apparatus 1.

As shown in the figure, the image-capturing apparatus 1 includes asystem controller 2, an image-capturing unit 3, an image-capturingcontroller 4, a display unit 5, a display controller 6, an operationinput unit 7, a storage unit 8, a communication unit 9, a speed detector10, and a bus 11.

The system controller 2 is formed by a microcomputer including, forexample, a CPU (Central Processing Unit), a ROM (Read Only Memory), aRAM (Random Access Memory), a non-volatile memory unit, and an interfaceunit, and serves as a controller for controlling the entireimage-capturing apparatus 1. The system controller 2 performs variouskinds of computation processes and transmission and reception of acontrol signal with each unit via the bus 11 in accordance with aprogram stored in the internal ROM or the like, and causes each unit toperform a necessary operation.

The image-capturing unit 3 includes an image-capturing optical system 3a, an image-capturing element unit 3 b, and an image-capturing signalprocessor 3 c.

The image-capturing optical system 3 a in the image-capturing unit 3 isprovided with a lens system including the image-capturing lens 3L shownin FIG. 1, an aperture, a zoom lens, a focus lens, and the like; and adriving system for causing the lens system to perform a focus operationand a zoom operation.

In the image-capturing element unit 3 b in the image-capturing unit 3, asolid-state image-capturing element array for detecting image-capturinglight obtained by the image-capturing optical system 3 a and forgenerating an image-capturing signal by performing photoelectricconversion thereon is provided. The solid-state image-capturing elementarray is formed as, for example, a CCD (Charge Coupled Device) sensorarray or a CMOS (Complementary Metal Oxide Semiconductor) sensor array.

The image-capturing signal processor 3 c in the image-capturing unit 3includes a sample-hold/AGC (Automatic Gain Control) circuit forperforming gain adjustment and waveform shaping on a signal obtained bysolid-state image-capturing elements, and a video A/D converter, andobtains captured image data as digital data. Furthermore, awhite-balance process, a luminance process, a color signal process, andthe like are performed on the captured image data.

Image capturing is performed by the image-capturing unit 3 having theimage-capturing optical system 3 a, the image-capturing element unit 3b, and the image-capturing signal processor 3 c, and captured image datais obtained.

The image data obtained by the image-capturing operation of theimage-capturing unit 3 is processed by the image-capturing controller 4.

Under the control of the system controller 2, the image-capturingcontroller 4 performs a process for converting the captured image datainto a predetermined image data format and a process for supplying theconverted captured image data to the image analysis unit 12, the storageunit 9, and the display controller 6 in response to the operationstatus.

On the basis of the instruction of the system controller 2, theimage-capturing controller 4 performs on/off control of animage-capturing operation in the image-capturing unit 3, driving controlof a zoom lens and a focus lens of the image-capturing optical system 3a, control of the sensitivity of the image-capturing element unit 3 band the frame rate, parameter control of each process of theimage-capturing signal processor 3 c, and setting of executionprocesses.

For the configuration for performing display to a user in theimage-capturing apparatus 1, a display unit 5 and a display controller 6are provided.

The display unit 5 is provided with a display driving unit for driving aliquid-crystal display or the like. This display driving unit is formedof a pixel driving circuit for displaying image data supplied from theimage-capturing controller 4 on, for example, a liquid-crystal display.The pixel driving circuit applies, at a predeterminedhorizontal/vertical driving timing, a driving signal based on a videosignal to each of pixels arranged in a matrix in the liquid-crystaldisplay, so that display is performed.

Under the control of the system controller 2, the display controller 6drives a pixel driving circuit in the display unit 5 so as to performpredetermined display. That is, display as an image-capturing monitor inthe image-capturing unit 3 is performed.

In order to perform these displays, for example, luminance leveladjustment, color correction, contrast adjustment, sharpness (contourenhancement) adjustment, and the like can be performed. Furthermore,generation of an expanded image such that part of image data is expandedor generation of a reduced image, image effect processes, such as softfocus, mosaic, luminance inversion highlight display (enhancementdisplay) of part of an image, changing of atmosphere of the color of thewhole, and the like can be performed.

The operation input unit 7 has operation elements such as, for example,keys, buttons, and dials. For example, operation elements used inpower-supply on/off operation and used in an on/off operation of anautomatic image-capturing processing function (to be described later)are formed. Furthermore, operation elements used in the operation of theimage-capturing system, for example, shutter operation, zoom operation,exposure setting operation, self-timer image-capturing operation, andthe like may be formed.

The operation input unit 7 supplies information obtained from suchoperation elements to the system controller 2, and the system controller2 performs necessary computation processes and control corresponding tothese items of information.

The storage unit 8 is used to store various kinds of data. For example,the storage unit 8 is used to store captured image data.

This storage unit 8 may be formed of a solid-state memory such as aflash memory, and may also be formed of, for example, an HDD (Hard DiskDrive).

The storage unit 8, rather than being formed as an incorporatedrecording medium, may also be formed as a recording and reproductiondrive compatible with a portable recording medium, for example, a memorycard, an optical disc, a magneto-optical disc, a hologram memory, or thelike, in which a solid-state memory is contained.

Of course, both a built-in type memory, such as a solid-state memory oran HDD, and a recording and reproduction drive for a portable recordingmedium may be installed.

Under the control of the system controller 2, the storage unit 8 recordsand stores the captured image data.

Under the control of the system controller 2, the recorded data is read,and the data is supplied to the system controller 2, the displaycontroller 6, and the like.

The communication unit 9 is provided as a unit for performing datacommunication with various kinds of external devices.

For example, transmission and reception of data may be performed with aserver apparatus (not shown). In that case, for example, networkcommunication may be performed via a short-distance wirelesscommunication with respect to a network access point by using a method,such as, for example, a wireless LAN or Bluetooth or, for example,wireless communication may be performed directly with a server apparatushaving a compliant communication function.

Furthermore, the communication unit 9 may be connected to a device, suchas a personal computer, by using an interface, such as, for example, aUSB (Universal Serial Bus) method, so that transmission and reception ofdata is performed.

The communication unit 9 enables, for example, captured image data thatis captured and stored in the storage unit 8 to be transferred to apersonal computer or other external devices.

The speed detector 10 detects the movement speed of the image-capturingapparatus 1 and sends the detected speed information to the systemcontroller 2. In the case of the in-vehicle image-capturing apparatus 1shown in FIG. 1A, the movement speed of the image-capturing apparatus 1is the traveling speed of the automobile. Furthermore, in the case ofthe image-capturing apparatus 1 being of a type that the user wears asin FIGS. 1B and 1C, the movement speed of the image-capturing apparatus1 is the movement speed of the user.

The movement speed of the user is a movement speed that may be not onlythe speed of walking and running, but also the speed when the user ridesa bicycle, an automobile, an electric train, or the like.

For example, when the image-capturing apparatus 1 is disposed in avehicle, such as an automobile, the speed detector 10 can be configuredto detect vehicle-speed pulses of the vehicle.

The speed detector 10 is not limited to an in-vehicle type or a userwearing type, and can be constituted by, for example, a GPS (GlobalPositioning System) receiver, a WiFi (Wireless Fidelity) device, aposition detector using position information service provided by amobile phone company, and a computation circuit.

For example, by performing position detection at unit time intervals andby computing a movement distance as a difference of the position, it ispossible to compute the speed on the basis of the movement distance andthe unit time period.

The configuration of the image-capturing apparatus 1 has been describedabove, but this is only an example. Addition and deletion of variouscomponents are of course considered on the basis of examples ofoperations and functions, which are performed in practice.

3. Automatic Image-Capturing Processing Operation Example I

The image-capturing apparatus 1 of this example, which is shown as anexample in FIGS. 1A, 1B, and 1C, is configured in the manner describedabove. In particular, the system controller 2 performs control so thatimage capturing is performed automatically (without depending on ashutter operation by the user) and thereby, an operation of capturing animage as a drive log or a life log is performed. The image-capturingoperation refers to an operation of storing captured image data capturedby the image-capturing unit 3 in the storage unit 8.

Then, when this automatic image-capturing process function is used, anautomatic image-capturing processing operation is performed so that animage-capturing operation is performed at approximately fixed distanceintervals irrespective of the movement speed of the automobile and theuser.

An automatic image-capturing processing operation of this embodimentwill be described below. As the image-capturing apparatus 1 in automaticimage-capturing processing operation example I to be described hereinand automatic image-capturing processing operation examples II, III, IV,V, VI, and VII (to be described later), a type of image-capturingapparatus 1 disposed in an automobile, shown in FIG. 1A, is assumed anddescribed.

FIG. 3A shows changes in the speed of the image-capturing apparatus 1,in which the horizontal axis indicates the speed and the horizontal axisindicates the time.

Since the image-capturing apparatus 1 is disposed in an automobile, thespeed referred to herein indicates that the speed at which theautomobile travels is shown as the speed of the image-capturingapparatus 1. This also applies to the automatic image-capturingprocessing operation examples II, III, IV, V, VI, and VII (to bedescribed later).

The traveling speed of the automobile constantly changes. FIG. 3A showschanges in the speed of the automobile, that is, changes in the speed ofthe installed image-capturing apparatus 1. In this case, first, theautomobile transits at a low speed, the speed gradually increases, andafter a while, the automobile transits at a high speed.

In FIG. 3A, times at which an image-capturing operation is performed atfixed distance intervals in response to the speed of the image-capturingapparatus 1 are shown as points in time P1 to P9.

FIG. 3B also shows variations in the geographical distance at points intime P1 to P9 shown in FIG. 3A. Since the automobile (theimage-capturing apparatus 1) is moving, at points in time P1 to P9,image capturing is performed at different image-capturing places. Inthis case, the distance interval at each place at each of points in timeP1 to P9 is a distance Lx.

That is, if image-capturing operation times are assumed to be points intime P1 to P9 in FIG. 3A in response to the movement speed and itschange in the speed, it is possible for the image-capturing apparatus 1to perform image capturing at places at intervals of approximately fixeddistance intervals when viewed geographically.

The processing of the system controller 2 for implementing such anoperation will be described with reference to FIG. 4.

The processing shown in FIG. 4 is processing for controlling oneimage-capturing operation. As a result of repeating the processing fromthe start to the end in FIG. 4, automatic image capturing is performedin a continued manner. This processing is performed in accordance with aprogram stored in a ROM contained in the system controller 2 (this alsoapplies to the processing shown in FIGS. 5, 6, 7, 10, 13 and 14 (to bedescribed later)).

In step F101, the system controller 2 performs processing for resettinga variable Ln indicating the distance moved by the image-capturingapparatus 1 to an initial value 0 and for setting the movement distanceLn=0.

Then, in step F102, the system controller 2 resets a timer Tm, which isan internal timer, in order to set a count value=0 and also, starts thecounting of the timer Tm.

Next, in step F103, the system controller 2 obtains the current speed Vof the image-capturing apparatus 1 (the automobile having theimage-capturing apparatus 1 installed therein, etc.) from the speeddetector 10.

In step F104, the system controller 2 computes a movement distance onthe basis of the timer Tm in which counting has started in step F102 andon the basis of the speed V of the image-capturing apparatus 1, which isobtained in step F103. That is, on the basis of (speed V)×(time periodTm), the movement distance in the processing period of steps F102 toF104 is determined. By adding the current movement distance Ln to theabove movement distance, a new movement distance Ln is set.

At the initial processing point in time, Ln=0, and therefore, Ln=(speedV)×(time period Tm)+0. Thereafter, processing of steps F102, F103, andF104 is repeated through step F105. At the processing point in time ofstep F104, the movement distance during steps F102 to F104 is determinedby (speed V)×(time period Tm). Therefore, by adding the current movementdistance Ln to the above movement distance in order to determine a newmovement distance Ln, the movement distance Ln is a total movementdistance after the processing in step F101 has started.

In step F105, the system controller 2 determines whether or not thecurrent movement distance Ln determined in step F104 has reached apredetermined distance Lx shown in FIG. 3B.

When the system controller 2 determines in step F105 that the currentmovement distance Ln has not reached the distance Lx, the processreturns to step F102, and processing of steps F102, 103, and F104described above is performed.

When the movement distance Ln reaches the distance Lx, the systemcontroller 2 causes the process to proceed to step F106. In step F106,the system controller 2 issues instructions for performing animage-capturing operation. That is, an operation of obtaining capturedimage data by the image-capturing unit 3, predetermined signalprocessing, such as a compression process, by the image-capturingcontroller 4, an operation of transferring to the storage unit 8, and anoperation of recording on a recording medium in the storage unit 8 areperformed, and thus image capturing of one still image is performed.

After the performance of the image-capturing operation in step F106 hasbeen instructed, the system controller 2 performs the processing of FIG.4 again starting from step F101.

According to the processing of FIG. 4, an image-capturing operation isperformed in accordance with instructions for performing animage-capturing operation issued in step F106 at a time at which it isdetermined in step F105 that the image-capturing apparatus 1 has moved adistance equal to or greater than the distance Lx from the place wherethe image-capturing apparatus 1 performed the previous image-capturingoperation.

That is, each of points in time P1, P2, P3 . . . P9 of FIG. 3A is animage-capturing instruction time in step F106. Then, as a result, thedistance interval of the places at which image capturing is performed ateach time is an approximately fixed distance interval, which is adistance Lx as shown in FIG. 3B.

As described above, as a result of automatic image capturing beingperformed at approximately fixed distance intervals, which are each thedistance Lx, captured image data of scenery at approximately fixeddistance intervals is stored, which is preferable as a drive log.

4. Automatic Image-Capturing Processing Operation Example II

In the automatic image-capturing processing operation example Idescribed with reference to FIG. 4, while the image-capturing apparatus1 is moving, image-capturing operations are performed at distanceintervals, which are each approximately the distance Lx. By setting thedistance interval at which an image-capturing operation is performed inthis manner to be approximately fixed, it is possible to store capturedimage data in which the state of the subject has changed.

However, if an image-capturing operation is performed only in responseto an interval that is equal to or greater than the distance Lx beingreached after the image-capturing apparatus 1 performed the previousimage-capturing operation, there is a case in which an image-capturingoperation is performed too frequently.

For example, when an automobile having the image-capturing apparatus 1is moving at a high speed along a highway or the like, it is consideredthat the automobile might travel the distance Lx or more in a very shorttime period. In that case, image capturing is performed very frequently,and a large amount of captured image data is recorded in the storageunit 8 in a short time.

For the drive log camera or the life log camera for recording thetraveling of the automobile and everyday life of the user, if capturedimage data is recorded too frequently in the storage unit 8, theavailable capacity of the storage unit 8 could become insufficient. Inparticular, each place passed during high-speed movement may not be ofmuch value as an image to the user.

Therefore, whereas automatic image capturing is basically performed atintervals of the distance Lx as in the above-described automaticimage-capturing processing operation example I, the following processingoperation is considered in which, during high-speed movement, imagecapturing is not performed too frequently and the amount of capturedimage data to be recorded in the storage unit 8 is reduced.

A description will be given below, with reference to FIG. 5, of theprocessing of the system controller 2 for implementing such a processingoperation.

The system controller 2 repeats the processing of FIG. 5 during theexecution period of an automatic image-capturing operation.

Initially, in step F201, the system controller 2 resets a timer Tm2,which is an internal timer, in order to set the timer Tm2=0, and causesthe counting of the timer Tm2 to be started.

The timer Tm2 causes the counting to be started immediately after animage-capturing operation is performed in the image-capturing apparatus1, and is used to determine whether a predetermined time period haspassed from the time when the image-capturing operation was performed instep F207 (to be described later).

Then, in steps F202 to F206, the system controller 2 performs the sameprocessing operations as the processing operations from steps F101 toF105 described with reference to FIG. 4.

That is, initially, the system controller 2 performs processing forresetting the movement distance Ln of the image-capturing apparatus 1 toan initial value 0, and performs processing for resetting the timer Tm1,which is an internal timer, to an initial value 0 and starting counting.Then, processing for obtaining the speed V supplied from the speeddetector 10 as the speed V of the image-capturing apparatus 1,multiplying the value of the speed V with the value of the timer Tm1,and adding the value of the movement distance Ln to the value of themultiplied result is performed. After the movement distance Ln of theimage-capturing apparatus 1 is computed in the manner described above, aprocess for determining whether or not the movement distance Ln hasreached the distance Lx is performed. When a negative result isobtained, the process returns to step F203. Then, until a determinationresult that the movement distance Ln has reached the distance Lx at acertain point in time, processing of step F203→step F204→step F205→stepF206→step F203→ . . . is repeated.

Then, when the determination result that the movement distance Ln has amagnitude equal to or greater than the distance Lx is obtained, theprocess proceeds to step F207.

In step F207, the system controller 2 compares the count value of thetimer Tm2 with a preset shortest waiting time period Tmin. That is, itis determined whether or not the shortest waiting time period has passedfrom the time of the previous image capturing.

The shortest waiting time period Tmin is a time period that is providedas a minimum time period after which an image-capturing operation may beperformed even if the image-capturing apparatus 1 has already moved adistance equal to or greater than the distance Lx after theimage-capturing apparatus 1 performed the previous image-capturingoperation.

If the count value of the timer Tm2 has not reached the shortest waitingtime period Tmin, the system controller 2 waits in step F207 until theshortest waiting time period Tmin is reached.

Then, when the timer Tm2 has reached the shortest waiting time periodTmin or more at a certain point in time, the system controller 2 causesthe process to proceed to step F208.

In step F208, the system controller 2 issues instructions for performingan image-capturing operation. That is, the system controller 2 issuesinstructions for causing the image-capturing unit 3 to capture an imageof a subject, and causes the image-capturing controller 4 to retrievethe captured image data of one frame, to perform predeterminedprocessing thereon, and to transfer the captured image data to thestorage unit 8.

In the storage unit 8, a process for recording the transferred capturedimage data of one frame as a still image on a recording medium isperformed.

Thereafter, the system controller 2 repeats the processing of FIG. 5again starting from step F201.

That is, according to the processing of FIG. 5, an image-capturingoperation is performed when the movement of the distance Lx is detected.If the shortest waiting time period Tmin has not passed from theprevious image-capturing timing even if the movement of the distance Lxis detected, the image-capturing operation is performed after waitingfor the passage of the shortest waiting time period Tmin.

For this reason, even if the automobile is traveling at a high speed andthe distance Lx is traveled too quickly, in that case, image capturingat intervals of a fixed distance is not performed, the distanceintervals becoming wide to some extent, but image capturing at certaintimes is performed.

As a result, if the above is practised while image capturing is usuallyperformed at intervals of fixed distances, during high-speed traveling,the case in which image capturing is performed too frequently can beavoided, and the amount of captured image data to be recorded in thestorage unit 8 can be reduced to an appropriate amount.

5. Automatic Image-Capturing Processing Operation Example III

In the above-described automatic image-capturing processing operationexamples I and II of FIGS. 4 and 5, while the image-capturing apparatus1 is moving, captured image data in which the state of the subject haschanged is obtained by performing an image-capturing operation inresponse to the distance Lx or more being passed after theimage-capturing apparatus 1 performed the previous image-capturingoperation.

Furthermore, in the automatic image-capturing processing operationexample II of FIG. 5, when the movement speed of the image-capturingapparatus 1 is high and the image-capturing apparatus 1 moves thedistance Lx or more in a short time, in order to prevent a large amountof captured image data from being recorded in the storage unit 8, animage-capturing operation is performed when the shortest waiting timeperiod Tmin or more has passed after the image-capturing apparatus 1performed the previous image-capturing operation.

As described above, in the automatic image-capturing processingoperation example II, it is possible to store captured image data inwhich the state of a subject has changed, and by providing the shortestwaiting time period Tmin in such a manner as to cope with a case inwhich the speed of the image-capturing apparatus 1 is high, the amountof captured image data to be recorded in the storage unit 8 is reduced.

However, usually, regarding the speed at which an automobile travels,the speed is considered to vary frequently, for example, becoming highor low.

For example, when the speed of the automobile in which theimage-capturing apparatus 1 is disposed is low or the automobile isstopped, the image-capturing apparatus 1 is moving at a low speed or isstopped. Then, it takes a considerable amount of time to move a distanceequal to or greater than the distance Lx from the place where theimage-capturing apparatus 1 performed the previous image-capturingoperation, or it is difficult to move a distance equal to or greaterthan the distance Lx, and thus a case may occur in which animage-capturing operation time is not reached soon enough.

At such a time, if an image-capturing operation is not performed becausethe image-capturing apparatus 1 has not moved a distance equal to orgreater than the distance Lx, this is not so appropriate for theintended use of the life log camera for recording the daily life of theuser.

Furthermore, even if not accompanied by the movement of a distance, thescenery around the subject may change with the passage of time. As aconsequence, even if the distance has not changed much, the user has apossibility of obtaining a valuable image for the drive log or life log.

Therefore, it is considered that a fixed time interval (longest waitingtime) is provided as a time interval at which image-capturing operationsare performed in such a manner as to deal with a case in which themovement speed of the image-capturing apparatus 1 is low or theimage-capturing apparatus 1 is stopped. That is, the followingprocessing operation is considered in which, whereas automatic imagecapturing is basically performed at intervals of the distance Lx as inthe above-described automatic image-capturing processing operationexample I, the case in which an image-capturing time is not reached dueto a situation of low-speed traveling or stopping does not occur.

A description will be given below, with reference to FIG. 6, of theprocessing of the system controller 2 for implementing such a processingoperation. During the execution period of an automatic image-capturingoperation, the system controller 2 repeatedly performs the processing ofFIG. 6.

Initially, in step F301, the system controller 2 resets a timer Tm2,which is an internal timer, in order to set the timer Tm2=0, and causesthe counting of the timer Tm2 to be started.

The timer Tm2 is used to start counting immediately after theimage-capturing operation is performed in the image-capturing apparatus1, and is used to determine whether or not a predetermined time periodor more has passed from the time when the image-capturing operation wasperformed in step F307 (to be described later).

Thereafter, the system controller 2 performs the processing operationsfrom steps F302 to F305, which are the same processing operations assteps F202 to F205 described with reference to FIG. 5 above.

That is, initially, the system controller 2 resets the timer Tm2, whichis an internal timer, to an initial value 0 and thereafter causescounting to be started. Then, the movement distance Ln of theimage-capturing apparatus 1 is reset to an initial value 0, and afterthe timer Tm1, which is an internal timer, is reset to an initial value0, counting is started. Furthermore, processing for obtaining the speedV supplied from the speed detector 10 as the speed V of theimage-capturing apparatus 1, for multiplying the value of the speed Vwith the value of the timer Tm1, and for adding the value of themultiplied result to the value of the movement distance Ln is performed.In the manner described above, the movement distance Ln of theimage-capturing apparatus 1 is computed.

Then, in step F306, the system controller 2 determines whether or notthe movement distance Ln of the image-capturing apparatus 1 has reachedthe distance Lx.

When it is determined in step F306 that the movement distance Ln hasreached the distance Lx, the process proceeds to step F308.

In step F308, the system controller 2 issues instructions for performingan image-capturing operation similarly to the process of step F208 ofFIG. 4 above.

That is, the system controller 2 issues instructions for causing theimage-capturing unit 3 to capture an image of a subject, and performsprocessing for causing the image-capturing controller 4 to retrieve thecaptured image data of one frame, to perform predetermined processingthereon, transferring the captured image data to the storage unit 8, andrecording, as a still image, the transferred captured image data of oneframe on a recording medium of the storage unit 8.

Then, the processing of FIG. 6 is repeated starting from step F301.

On the other hand, when it is determined in step F306 that the movementdistance Ln has not yet reached the distance Lx, the system controller 2causes the process to proceed to step F307.

In step F307, the system controller 2 determines whether or not thecount value of the timer Tm2 is greater than the longest waiting timeperiod Tmax.

The longest waiting time period refers to that which is set as a time atwhich image capturing is performed even if the image-capturing apparatus1 has not moved a distance equal to or greater than the distance Lx fromthe place where the image-capturing apparatus 1 performed the previousimage-capturing operation.

When the system controller 2 determines that the count value of thetimer Tm2 is smaller than the longest waiting time period Tmax, theprocess returns to step F303.

However, when it is determined in step F306 that the movement distanceLn has not reached the distance Lx, but it is determined in step F307that the longest waiting time period is reached, the process proceeds tostep F308, where the performance of an image-capturing operation isinstructed as described above. As a result, even if the movementdistance Ln has not reached the distance Lx, image capturing isperformed.

Thereafter, the system controller 2 returns to step F301, whereprocessing is repeated.

According to the above-described processing of FIG. 6, similarly to theprocessing of FIGS. 4 and 5 described earlier, an image-capturingoperation is performed in response to the image-capturing apparatus 1being moved a distance equal to or greater than the distance Lx from theplace where the image-capturing apparatus 1 performed the previousimage-capturing operation, and thus captured image data in which thestate of the subject has changed can be obtained.

Furthermore, when the movement of the distance Lx or more is notperformed soon enough, such as when the speed of the image-capturingapparatus 1 is low or the image-capturing apparatus 1 is stopped, if thelongest waiting time period Tmax has passed from the time when theprevious image capturing was performed, image capturing is performedregardless of the moved distance, thereby making it possible to avoid asituation in which an image-capturing operation is not performed for along time.

As a result, image capturing suitable as a drive log and a life log isimplemented.

Furthermore, if image capturing is not performed due to, for example, astopped state, a case in which the failure of the image-capturingapparatus 1 is suspected by the user can occur, and such a situation canbe avoided.

6. Automatic Image-Capturing Processing Operation Example IV

In the above-described automatic image-capturing processing operationexample II of FIG. 5, by performing an image-capturing operation inresponse to the shortest waiting time period Tmin being passed after theimage-capturing apparatus 1 has moved the distance Lx or more from theplace where the image-capturing apparatus 1 performed the previousimage-capturing operation has been performed so as to cope with a casein which the speed of the image-capturing apparatus 1 is high, theamount of the captured image data to be recorded in the storage unit 8is reduced.

Furthermore, in the automatic image-capturing processing operationexample III of FIG. 6, when the image-capturing apparatus 1 has notmoved the distance Lx or more from the place where the image-capturingapparatus 1 performed the previous image-capturing operation in such amanner as to cope with a case in which the speed of the image-capturingapparatus 1 is low or the image-capturing apparatus 1 is stopped, animage-capturing operation is performed in response to the passage of thelongest waiting time period Tmax. As a result of the above, it ispossible to obtain captured image data in which the state on the subjectside could have changed as a result of an elapse of a time period afterthe image-capturing apparatus 1 performed the previous image-capturingoperation.

However, as described earlier, usually, there are cases in which thespeed of an automobile increases or decreases, or sometimes theautomobile is stopped while traveling, and the speed changes frequently.

For example, when an automobile travels along a highway, it isconsidered that the automobile travels at a speed higher than that in anordinary road. When the automobile gets off halfway to an ordinary roadand travels, there are cases in which the speed becomes low or theautomobile is stopped due to congestion of the road or a red trafficlight.

Therefore, the following processing operation is considered in whichboth the processing operation in which, in response to the above case,the image-capturing apparatus 1 performs an image-capturing operation inresponse to the passage of the shortest waiting time period Tmin afterthe image-capturing apparatus 1 moves the distance Lx or more from theplace where the image-capturing apparatus 1 performed the previousimage-capturing operation, and a processing operation in which theimage-capturing apparatus 1 performs an image-capturing operation inresponse to the passage of the longest waiting time period Tmax when theimage-capturing apparatus 1 has not moved the distance Lx or more, arecombined.

A description will be given below, with reference to FIG. 7, theprocessing of the system controller 2 for implementing such a processingoperation.

Initially, in FIG. 7, the system controller 2 performs the processingoperations from steps F401 to F406, which are the same processingoperations as steps F201 to F206 in FIG. 5 described earlier.

Then, when it is determined in step F406 that the movement distance Lnhas a magnitude equal to or greater than the distance Lx, the systemcontroller 2 causes the process to proceed to step F408.

In step F408, similarly to step F207 described with reference to FIG. 5,it is determined whether or not the time period Tm2 is greater than theshortest waiting time period Tmin.

That is, the system controller 2 performs a process for determiningwhether or not the shortest waiting time period Tmin that is provided asa minimum in order to perform an image-capturing operation after theimage-capturing apparatus 1 has moved a distance equal to or greaterthan the distance Lx after the image-capturing apparatus 1 performed theprevious image-capturing operation. Then, when it is determined that theshortest waiting time period Tmin has not passed, the system controller2 waits in step F408 until the count value of the timer Tm2 becomesequal to or greater than the shortest waiting time period Tmin.

Then, when it is determined that the shortest waiting time period haspassed, the system controller 2 causes the process to proceed to stepF409.

Furthermore, when it is determined in step F406 that the movementdistance Ln has not reached the distance Lx, the system controller 2causes the process to proceed to step F407. Similarly to step F307described with reference to FIG. 6, in step F407, the system controller2 determines whether or not the count value of the timer Tm2 has reachedthe longest waiting time period Tmax. If the longest waiting time periodhas not passed, the process returns to step F403.

On the other hand, if the longest waiting time period Tmax has passedeven while the image-capturing apparatus 1 is not recognized to havemoved the distance Lx or more from the place where the image-capturingapparatus 1 performed the previous image-capturing operation, theprocess proceeds from step F407 to step F409.

In step F409, the system controller 2 performs the same process as theprocess of step F208 of FIG. 5 described above, and performs apredetermined process on the captured image data of one frame andthereafter, performs a process for recording, as a still image, thecaptured image data of one frame on a recording medium of the storageunit 8.

According to such a processing of FIG. 7, similarly to the processingoperations of FIGS. 5 and 6 described above, the image-capturingapparatus 1 basically performs an image-capturing operation in responseto the image-capturing apparatus 1 being moved a distance equal to orgreater than the distance Lx from the place where the image-capturingapparatus 1 performed the previous image-capturing operation.

However, by performing an image-capturing operation in response to thepassage of the shortest waiting time period Tmin or more, it is possibleto avoid image capturing from being excessively performed duringhigh-speed movement, and thus the amount of captured image data to berecorded in the storage unit 8 is reduced.

Furthermore, by performing an image-capturing operation in response tothe passage of the longest waiting time period Tmax or more, a situationin which image capturing is not performed soon enough due to a low-speedmovement or a stopped state can be avoided.

7. Automatic Image-Capturing Processing Operation Example V

In the above-described automatic image-capturing processing operationexamples I, II, III, and IV of FIGS. 4, 5, 6, and 7, an image-capturingoperation is performed in response to the image-capturing apparatus 1being moved the distance Lx or more after the image-capturing apparatus1 performed the previous image-capturing operation, and the capturedimage data is recorded in the storage unit 8.

However, if the image-capturing apparatus 1 performs an image-capturingoperation in response to the image-capturing apparatus 1 being moved thedistance Lx or more, it is considered that the amount of captured imagedata that is captured during that period could be a considerable amount.Furthermore, when the movement speed of the image-capturing apparatus 1is high and the image-capturing apparatus 1 moves the distance Lx ormore in a short time, the image-capturing operation is frequentlyperformed in a short time, and it is considered that the amount ofcaptured image data to be recorded in the storage unit 8 increases.

Since the recording capacity of the storage unit 8 is limited, thereduction in the amount of captured image data to be recorded in thestorage unit 8 is preferable in the image-capturing apparatus 1.

The technique for reducing the amount of data should preferably be suchthat, for example, threshold values are provided for the time intervalat which an image-capturing operation is performed, the image size ofcaptured image data is decreased when the interval at which theimage-capturing operation is performed is short, the image size of thecaptured image data is increased when the interval at which theimage-capturing operation is performed is long, and the captured imagedata is recorded in the storage unit 8.

Such an automatic image-capturing processing operation will be describedbelow.

FIG. 8 shows the relationship between the movement speed of theimage-capturing apparatus 1 and the image size when captured image datais to be recorded in the storage unit 8 in this embodiment, in which thehorizontal axis indicates the image size and the horizontal axisindicates the speed.

In FIG. 8, if the movement speed of the image-capturing apparatus 1 islow, the image size is changed to be increased, and if the movementspeed of the image-capturing apparatus 1 is high, the image size ischanged to be decreased, and the captured image data is recorded in thestorage unit 8. That is, when the movement speed is low, a long time istaken to reach a fixed distance, the image-capturing time intervalbecomes long, and the number of the image capturing chances decreases.Conversely, if the movement speed is high, a short time is taken toreach a fixed distance, the image-capturing time interval becomes short,the image-capturing time interval decreases, and image capturing isperformed frequently. For this reason, by changing the size of the imagesize to be stored in response to the movement speed so that the higherthe movement speed, the more the image size is decreased, it is possibleto efficiently save the recording capacity of the storage unit 8 asdescribed above.

FIG. 9 shows a specific technique of setting an image size. Thehorizontal axis indicates the image-capturing time interval, and thehorizontal axis indicates the image size.

This case shows that a threshold value for a time interval in which animage-capturing operation is performed is provided, so that the imagesize of captured image data to be stored is changed on the basis of thethreshold value.

As shown in the figure, for example, three threshold values are providedfor the time interval at which an image-capturing operation isperformed. On the basis of the threshold value of the time interval atwhich an image-capturing operation has been performed, captured imagedata to be stored is determined from among image sizes of four levels.

That is, when an image-capturing operation is performed in response tothe image-capturing apparatus 1 being moved the distance Lx or moreafter the image-capturing apparatus 1 performed the previousimage-capturing operation, in the case that the time interval is smallerthan or equal to a threshold value Th1, which is the shortest thresholdvalue, the captured image data is stored at an image size sz1.

Furthermore, if the image-capturing time interval is between a thresholdvalue Th1 and a threshold value Th2, the captured image data is storedat an image size sz2. If the image-capturing time interval is betweenthe threshold value Th2 and a threshold value Th3, the captured imagedata is stored at an image size sz3. If the image-capturing timeinterval is greater than or equal to the threshold value Th3, thecaptured image data is stored at an image size sz4.

A description will be given below, with reference to FIG. 10, of theprocessing of the system controller 2 for implementing such anoperation.

Initially, in steps F501 to F506 in FIG. 10, the system controller 2performs the same processing operations as the processing operations ofsteps F201 to F206 in FIG. 5 described earlier.

Then, when it is determined in step F506 that the distance Ln moved bythe image-capturing apparatus 1 after the image-capturing apparatus 1performed the previous image-capturing operation is a magnitude equal toor greater than the distance Lx, the system controller 2 causes theprocess to proceed to step F507.

In step F507, the system controller 2 performs a process for determiningwhether or not the count value of the timer Tm2 that started in stepF501 is smaller than or equal to the threshold value Th1 of a timeinterval.

Then, when it is determined that the count value of the timer Tm2 issmaller than or equal to the threshold value Th1, the process proceedsto step F508.

In step F508, the system controller 2 instructs the image-capturingcontroller 4 to set the image size sz1, which is the smallest size amongthe sizes sz1 to sz4 of the captured image data shown in FIG. 9. Then,the process proceeds to step F514.

Furthermore, when it is determined in step F507 that the count value ofthe timer Tm2 is greater than the threshold value Th1, in step F509, thesystem controller 2 performs a process for determining whether or notthe count value of the timer Tm2 is smaller than or equal to a thresholdvalue Th2.

Then, when it is determined in step F509 that the count value of thetimer Tm2 is smaller than or equal to the threshold value Th2, in stepF510, the system controller 2 instructs the image-capturing controller 4to set the image size sz2 as the size of captured image data. The imagesize sz2 is an image size that is large next to the image size sz1.Then, the process proceeds to step F514.

When it is determined in step F509 that the count value of the timer Tm2is greater than the threshold value Th2, the process proceeds to stepF511. In step F511, the system controller 2 performs a process fordetermining whether or not the count value of the timer Tm2 is smallerthan or equal to a threshold value Th3.

When it is determined in step F511 that the count value of the timer Tm2is smaller than or equal to the threshold value Th3, the systemcontroller 2 causes the process to proceed to step F512, where thesystem controller 2 instructs the image-capturing controller 4 to setthe image size sz3 as the size of the captured image data.

The image size sz3 is an image size that is the next largest image sizeafter the image size sz2. The process then proceeds to step F514.

Furthermore, when it is determined in step F511 that the count value ofthe timer Tm2 is greater than the threshold value Th3, the systemcontroller 2 causes the process to proceed to step F513, where thesystem controller 2 instructs the image-capturing controller 4 to set animage size sz4 as the size of the captured image data. The image sizesz4 is the largest image size. The process then proceeds to step F514.

In step F514, the system controller 2 issues instructions for performingan image-capturing operation. That is, the system controller 2 instructsthe image-capturing unit 3 to capture an image of a subject, and causesthe image-capturing controller 4 to retrieve the captured image data ofone frame, to perform predetermined process thereon, and to transfer thecaptured image data to the storage unit 8. At this time, theimage-capturing controller 4 processes the captured image data having animage size set in one of steps F508, F510, F512, and F513. In thestorage unit 8, a process is performed for recording the transferredcaptured image data of one frame as a still image on a recording medium.

The system controller 2 instructs the performance of an image-capturingoperation in step F514, and then starts processing from step F501 again.

As described above, by changing the image size of captured image data tobe stored in accordance with the image-capturing time interval,efficient use of the recording capacity of the storage unit 8 can beachieved.

The image obtained at a comparatively long time interval is consideredto have a high value for the image, and storing such an image at a largesize is preferable.

In this example, the captured image data is recorded in the storage unit8 in such a manner as to be divided into image sizes of four levels. Thecaptured image data may be divided into image sizes of two, three, fiveor more levels, and may be recorded.

8. Automatic Image-Capturing Processing Operation Example VI

In the above-described automatic image-capturing processing operationexample V of FIG. 10, the image size is changed on the basis of the timeinterval after the image-capturing apparatus 1 performed the previousimage-capturing operation, so that the amount of the captured image datato be recorded in the storage unit 8 is saved. However, a technique isalso possible in which, by changing, rather than the image size, thecompression ratio of captured image data on the basis of the timeinterval, the amount of captured image data to be recorded in thestorage unit 8 is saved.

Here, an automatic image-capturing processing operation in which acompression ratio is changed in the manner described above will bedescribed below.

FIG. 11 shows the relationship between the movement speed of theimage-capturing apparatus 1 and the compression ratio of captured imagedata when the captured image data is to be recorded in the storage unit8. The horizontal axis indicates the compression ratio, and thehorizontal axis indicates the speed. As shown in FIG. 11, if themovement speed of the image-capturing apparatus 1 is low, it takes timeto reach a fixed distance, and the number of image capturing chancesdecreases; therefore, the captured image data is recorded in the storageunit 8 at a low compression ratio (the amount of data is large and at ahigh image quality). On the other hand, as the movement speed increases,the time taken to reach a fixed distance becomes smaller, and the numberof image capturing chance increases; therefore, the captured image datais recorded in the storage unit 8 at a high compression ratio (theamount of data is small and at a low image quality). As a result, it ispossible to efficiently save the recording capacity of the storage unit8 as in the example described with reference to FIG. 10 above.

A specific technique is shown in FIG. 12. The horizontal axis indicatesthe time, and the horizontal axis indicates the compression ratio.Threshold values are provided for the time interval in the case that animage-capturing operation is performed, and the compression ratio ofcaptured image data to be stored is changed on the basis of thethreshold value.

For example, three threshold values are provided for the time intervalin the case that an image-capturing operation is performed, and on thebasis of the threshold values for the time interval at which theimage-capturing operation has been performed, compression ratios at fourlevels are determined with regard to the captured image data.

When the image-capturing apparatus 1 performs an image-capturingoperation in response to the image-capturing apparatus 1 being moved thedistance Lx or more after the image-capturing apparatus 1 performed theprevious image-capturing operation, in the case that the time intervalis smaller than or equal to the threshold value Th1, which is theshortest threshold value, the captured image data is compressed at thehighest compression ratio qt1 and is stored.

Furthermore, if the image-capturing time interval is between thethreshold value Th1 and the threshold values Th2, the captured imagedata is compressed at a compression ratio qt2 and is stored. If theimage-capturing time interval is between the threshold value Th2 and thethreshold value Th3, the captured image data is compressed at acompression ratio qt3 and is stored. If the image-capturing timeinterval is greater than or equal to the threshold value Th3, thecaptured image data is compressed at the lowest compression ratio qt4and is stored.

A description will be given below, with reference to FIG. 13, of theprocessing of the system controller 2 for implementing such anoperation.

Initially, in steps F601 to F606 in FIG. 13, the system controller 2performs the same processing operations as the processing operations ofsteps F201 to F206 in FIG. 5 described earlier.

Then, when it is determined in step F606 that the distance Ln moved bythe image-capturing apparatus 1 after the image-capturing apparatus 1performed the previous image-capturing operation is a magnitude equal toor greater than the distance Lx, the system controller 2 causes theprocess to proceed to step F607.

In step F607, the system controller 2 performs a process for determiningwhether or not the count value of the timer Tm2 that started in stepF601 is smaller than or equal to the threshold value Th1 of the timeinterval. Then, when it is determined that the count value of the timerTm2 is smaller than or equal to the threshold value Th1, the processproceeds to step F608.

In step F608, the system controller 2 indicates to the image-capturingcontroller 4 the highest compression ratio qt1 among the compressionratios qt1 to qt4 shown in FIG. 12. The process then proceeds to stepF614.

Furthermore, when it is determined in step F607 that the count value ofthe timer Tm2 is greater than the threshold value Th1, in step F609, thesystem controller 2 performs a process for determining whether or notthe count value of the timer Tm2 is smaller than or equal to thethreshold value Th2.

Then, when it is determined in step F609 that the count value of thetimer Tm2 is smaller than or equal to the threshold value Th2, in stepF610, the system controller 2 indicates the compression ratio qt2 to theimage-capturing controller 4. The compression ratio qt2 is a compressionratio that is the next lowest compression ratio after the compressionratio qt1. The process then proceeds to step F614.

Furthermore, when it is determined in step F609 that the count value ofthe timer Tm2 is greater than the threshold value Th2, the processproceeds to step F611. In step F611, the system controller 2 performs aprocess for determining whether or not the count value of the timer Tm2is smaller than or equal to the threshold value Th3.

Then, when it is determined in step F611 that the count value of thetimer Tm2 is smaller than or equal to the threshold value Th3, thesystem controller 2 causes the process to proceed to step F612, wherethe compression ratio qt3 is indicated to the image-capturing controller4. The compression ratio qt3 is a compression ratio that is the nextlowest compression ratio after the compression ratio qt2. The processthen proceeds to step F614.

Furthermore, when it is determined in step F611 that the count value ofthe timer Tm2 is greater than the threshold value Th3, the systemcontroller 2 causes the process to proceed to step F613, where thecompression ratio qt4 is indicated to the image-capturing controller 4.The compression ratio qt4 is the lowest compression ratio.

The process then proceeds to step F614.

In step F614, the system controller 2 issues instructions for performingan image-capturing operation. That is, the system controller 2 instructsthe image-capturing unit 3 to capture an image of a subject, and causesthe image-capturing controller 4 to retrieve the captured image data ofone frame, to perform a predetermined process thereon, and to transferthe captured image data to the storage unit 8. At this time, theimage-capturing controller 4 performs a process for compressing thecaptured image data at a compression ratio that is set in one of stepsF608, F610, F612, and F613. Then, in the storage unit 8, a process forrecording the transferred captured image data of one frame as a stillimage on a recording medium is performed.

After the system controller 2 instructs the performance of animage-capturing operation in step F614, the image-capturing apparatus 1starts processing from step F601 again.

As described above, by changing the compression ratio of the capturedimage data to be stored on the basis of the image-capturing timeinterval, the recording capacity of the storage unit 8 can beefficiently used.

Furthermore, it can be considered that an image obtained at acomparatively long time interval has a comparatively high valueregarding the image, and storage of such an image at a low compressionratio at a high image quality is preferable.

In this example, regarding a process for compressing captured imagedata, switching is performed among the compression ratios at fourlevels. Alternatively, the captured image data may be switched amongtwo, three, five or more levels.

Furthermore, in the case of achieving the highest image quality (in thecase that the time interval is longest), the captured image data may benot compressed.

9. Automatic Image-Capturing Processing Operation Example VII

In the automatic image-capturing processing operation examples I, II,III, IV, V, and VI described thus far of FIGS. 4, 5, 6, 7, 10, and 13,an image-capturing operation is performed in response to theimage-capturing apparatus 1 being moved the distance Lx or more afterthe image-capturing apparatus 1 performed the previous image-capturingoperation, and captured image data of one frame is recorded as a stillimage in the storage unit 8.

However, it is considered that captured image data to be recorded in thestorage unit 8 is recorded as moving images in addition to still images.

When a driving history and scenery of the daily life of a user are to berecorded as a drive log camera or a life log camera, making a record asmoving images can produce a record having a higher sense of realism thanone using still images. Furthermore, in still images, the time intervalat which the image-capturing apparatus 1 performs an image-capturingoperation is longer than in moving images, and there is a period inwhich an image of a subject is not captured. However, in moving images,since such a period in which it is difficult to capture an image of asubject is shorter than that in still images, it is possible tothoroughly record the daily life of the user, and a more preferablerecording of the scenery of the daily life can be made.

However, when all the daily life of the user is to be recorded as movingimages, a very large amount of captured image data is recorded in thestorage unit 8, and it is considered that the recording capacity of thestorage unit 8 is exceeded. Therefore, if captured image data to berecorded in the storage unit 8 is switched and recorded between stillimages and moving images in accordance with the situation, it ispossible to save the recording capacity of the storage unit 8.

For example, a processing operation is also considered in which, when animage-capturing operation is performed in response to theimage-capturing apparatus 1 being moved the distance Lx or more from theplace where the image-capturing apparatus 1 performed the previousimage-capturing operation, image capturing is performed in the form ofmoving images when image capturing is to be performed at a point in timeshorter than or equal to a predetermined time interval, and imagecapturing is performed in the form of still images when image capturingis to be performed at a point in time longer than or equal to thepredetermined time interval.

A description will be given below, with reference to FIG. 14, of theprocessing of the system controller 2 for implementing such a processingoperation.

Initially, the system controller 2 performs the processing operations ofsteps F701 to F706 in FIG. 14, which are the same as the processingoperations of steps F201 to F206 in FIG. 5. Then, when it is determinedin step F706 that the distance Ln moved after the previousimage-capturing operation was performed is greater than or equal to thedistance Lx, the system controller 2 causes the process to proceed tostep F707.

In step F707, the system controller 2 performs a process for determiningwhether or not the count value of the timer Tm2 is smaller than or equalto a predetermined time period Tx. The time period Tx is a thresholdvalue for the period from the time when the previous image-capturingoperation was performed.

When it is determined that the count value of the timer Tm2 is smallerthan or equal to the time period Tx, the system controller 2 causes theprocess to proceed to step F709.

In step F709, the system controller 2 issues instructions for performingan image-capturing operation in the form of moving images. That is, thesystem controller 2 instructs the image-capturing unit 3 to captureimage data of, for example, 30 frames per second, and causes theimage-capturing controller 4 to retrieve the captured image data andcompress it in accordance with the MPEG2 method, and to transfer thecompressed moving image data to the storage unit 8. Then, the systemcontroller 2 causes the storage unit 8 to record, as moving images, thetransferred captured image data on a recording medium.

Furthermore, when it is determined in step F707 that the count value ofthe timer Tm2 is greater than the time period Tx, the system controller2 causes the process to proceed to step F708.

In step F708, the system controller 2 issues instructions for performingan image-capturing operation in the form of still images. That is, thesystem controller 2 instructs the image-capturing unit 3 to capture animage of a subject, and causes the image-capturing controller 4 toretrieve the captured image data of one frame, to perform a process forcompressing the captured image data in accordance with the JPEG method,and to transfer it to the storage unit 8. Then, the system controller 2causes the storage unit 8 to record, as a still image, the transferredcaptured image data of one frame on a recording medium.

After the process of step F708 or F709, the system controller 2 returnsto step F701 and performs processing in a similar manner.

According to such a processing, when the movement is comparatively slow,still images are recorded at intervals of a fixed distance Lx. In thecase of high-speed movement in which a fixed distance Lx is reachedwithin the time period Tx, a moving image is recorded.

When the captured image is stored as a moving image, the subject can beviewed as moving more smoothly when it is reproduced later, than when itis stored as a still image and scenery having a sense of realism can berecorded. However, a large amount of the recording capacity is consumed.Therefore, during high-speed movement in which the image-capturingapparatus 1 moves the distance Lx in the time period of the time periodTx or less, moving-image capturing is performed, and when it takes timeto move the distance Lx, a switch is made to still images, therebysaving the capacity.

10. Modification

The embodiments of the present invention have thus been described. Thepresent invention should not be limited to any of the above-describedembodiments.

Each of the above-described examples has been basically described usingan in-vehicle image-capturing apparatus 1 shown in FIG. 1A. Theprocessing of each of the automatic image-capturing processing operationexamples I, II, III, IV, V, VI, and VII can be applied the same to theimage-capturing apparatus 1 of a type worn by the user as shown in FIGS.1B and 1C. As a result, a life log camera for appropriately recordingthe daily life of the user can be implemented.

Furthermore, when scenery of the daily life of the user and sceneryduring driving are to be recorded as captured image data by being usedas a life log camera or a drive log camera, audio may also be recordedsimultaneously. In that case, the image-capturing apparatus 1 may beprovided with a microphone and an audio processor, so that audio data isrecorded together with images.

As a technique in which the amount of captured image data to be recordedin the storage unit 8 is reduced and the recording capacity of thestorage unit 8 is saved, a technique of combining the processingexamples of the automatic image-capturing processing operation examplesV and VI described with reference to FIGS. 10 and 13 is also possible.For example, in the process of step F508 of FIG. 10 described above, aprocessing operation in which the image size of captured image data isset to an image size sz1 and the compression ratio is set to acompression ratio qt1 is possible. Furthermore, in step F510 of FIG. 10described above, a processing operation in which captured image data hasan image size sz2 and the compression ratio is set to a compressionratio qt2 is possible. In step F512, a processing operation in whichcaptured image data has an image size sz3 and the compression ratio isset to a compression ratio qt3 is possible. In step F513, a processingoperation in which captured image data has an image size sz4 and thecompression ratio is set to a compression ratio qt4 is possible.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents hereof.

1. An image-capturing apparatus comprising: image-capturing means forcapturing image data of a subject and for storing the captured imagedata in an image-capturing operation; speed detection means fordetecting speed information; and control means for controlling theimage-capturing means so that, in an automatic image-capturing processthat is not based on a shutter operation of a user, a distance moved bythe image-capturing apparatus is computed on the basis of the speedinformation from the speed detection means, and the image-capturingoperation is performed in response to a computation result indicatingthat the image-capturing apparatus has moved a predetermined distancebeing obtained.
 2. The image-capturing apparatus according to claim 1,wherein the control means sets a shortest waiting time period as a timeperiod from the time when the image-capturing operation is performed inthe image-capturing means, and if the shortest waiting time period hasnot passed when the computation result indicating that theimage-capturing apparatus has moved the predetermined distance isobtained on the basis of the speed detection information from the speeddetection means, the control means causes the image-capturing means toperform an image-capturing operation after the shortest waiting timeperiod has elapsed.
 3. The image-capturing apparatus according to claim1, wherein the control means sets a longest waiting time period as atime period from the time when the image-capturing operation isperformed in the image-capturing means, and when the longest waitingtime period has passed before the computation result, indicating thatthe image-capturing apparatus has moved the predetermined distance, isobtained on the basis of the speed detection information from the speeddetection means, the control means causes the image-capturing means toperform an image-capturing operation in response to the passage of thelongest waiting time period.
 4. The image-capturing apparatus accordingto claim 1, wherein the control means sets a shortest waiting timeperiod and a longest waiting time period as time periods from the timewhen the image-capturing operation is performed in the image-capturingmeans, if the shortest waiting time period has not passed when thecomputation result, indicating that the image-capturing apparatus hasmoved the predetermined distance, is obtained on the basis of the speeddetection information from the speed detection means, the control meanscauses the image-capturing means to perform an image-capturing operationafter the shortest waiting time period has elapsed, and when the longestwaiting time period has passed before the computation result indicatingthat the image-capturing apparatus has moved the predetermined distance,is obtained on the basis of the speed detection information from thespeed detection means, the control means causes the image-capturingmeans to perform an image-capturing operation in response to passage ofthe longest waiting time period.
 5. The image-capturing apparatusaccording to claim 1, wherein, when the computation result indicatingthat the image-capturing apparatus has moved the predetermined distanceis obtained on the basis of the speed detection information from thespeed detection means, the control means instructs a change of an imagesize in the image-capturing operation of the image-capturing means onthe basis of a time period elapsed after the image-capturing operationis performed in the image-capturing means.
 6. The image-capturingapparatus according to claim 1, wherein, when the computation result,indicating that the image-capturing apparatus has moved thepredetermined distance, is obtained on the basis of the speed detectioninformation from the speed detection means, the control means instructsa change of a compression ratio in the image-capturing operation of theimage-capturing means on the basis of a time period elapsed after theimage-capturing operation is performed in the image-capturing means. 7.The image-capturing apparatus according to claim 1, wherein, when thecomputation result, indicating that the image-capturing apparatus hasmoved the predetermined distance, is obtained on the basis of the speeddetection information from the speed detection means, the control meansinstructs a switching between a still-image capturing operation and amoving-image capturing operation as the image-capturing operation of theimage-capturing means on the basis of a time period elapsed after theimage-capturing operation is performed in the image-capturing means. 8.An image-capturing method for use with an image-capturing apparatus forperforming an automatic image-capturing process that is not based on ashutter operation of a user, the image-capturing method comprising:detecting speed information; computing a distance moved by theimage-capturing apparatus on the basis of the speed information; andcapturing image data of a subject and storing the captured image data inan image-capturing operation in response to a computation resultindicating that the image-capturing apparatus has moved a predetermineddistance being obtained.
 9. An image-capturing apparatus comprising: animage-capturing unit configured to capture image data of a subject andto store the captured image data in an image-capturing operation; aspeed detector configured to detect speed information; and a controllerconfigured to control the image-capturing unit so that, in an automaticimage-capturing process that is not based on a shutter operation of auser, a distance moved by the image-capturing apparatus is computed onthe basis of information from the speed detector, and theimage-capturing operation is performed in response to a computationresult indicating that the image-capturing apparatus has moved apredetermined distance being obtained.